1. These markings are not apparent in the photograph.
2. They appear black in the figure but are white in the actual specimen.
3. Pyorrhea: Definition and Classification;Simonton;Dent. Cosmos,1926
4. For description of microscopic findings on the paradontal tissues, compare Simonton, F. V.: The Etiology of Parodontoclasia, J.A.D.A., to be published.
5. They are altered, of course, by disease, such as caries or scurvy, (compare Höjer, A., and Westin, G.: Dent. Cosmos, 67: 1 (Jan.) 1925 or by attrition.